<template> 
  <div>
    <el-upload
      action="http://gulimall-taoyuanyuan.oss-cn-shenzhen.aliyuncs.com"
      :data="dataObj"
      list-type="picture"
      :multiple="false"
      :show-file-list="showFileList"
      :file-list="fileList"
      :before-upload="beforeUpload"
      :on-remove="handleRemove"
      :on-success="handleUploadSuccess"
      :on-preview="handlePreview">
      <el-button size="small" type="primary">点击上传</el-button>
      <div slot="tip" class="el-upload__tip">只能上传jpg/png文件，且不超过10MB</div>
    </el-upload>
    <el-dialog :visible.sync="dialogVisible">
      <img width="100%" :src="fileList[0].url" alt="">
    </el-dialog>
  </div>
</template>
<script>
  import { policy } from './policy'
  import { getUUID } from '@/utils'

  export default {
    name: 'singleUpload',
    props: {
      value: String
    },
    computed: {
      imageUrl () {
        return this.value
      },
      imageName () {
        if (this.value != null && this.value !== '') {
          return this.value.substr(this.value.lastIndexOf('/') + 1)
        } else {
          return null
        }
      },
      fileList () {
        return [{
          name: this.imageName,
          url: this.imageUrl
        }]
      },
      showFileList: {
        get: function () {
          return this.value != null && this.value !== '' && this.value !== undefined
        },
        set: function (newValue) {
        }
      }
    },
    data () {
      return {
        dataObj: {
          policy: '',
          signature: '',
          key: '',
          ossaccessKeyId: '',
          dir: '',
          host: ''
          // callback:'',
        },
        dialogVisible: false
      }
    },
    methods: {
      emitInput (val) {
        this.$emit('input', val)
      },
      handleRemove (file, fileList) {
        this.emitInput('')
      },
      handlePreview (file) {
        this.dialogVisible = true
      },
      beforeUpload (file) {
        let _self = this
        return new Promise((resolve, reject) => {
          policy().then(response => {
            _self.dataObj.policy = response.data.policy
            _self.dataObj.signature = response.data.signature
            _self.dataObj.ossaccessKeyId = response.data.accessid
            _self.dataObj.key = response.data.dir + '/' + getUUID() + '_${filename}'
            _self.dataObj.dir = response.data.dir
            _self.dataObj.host = response.data.host
            console.log(response)
            resolve(true)
          }).catch(err => {
            console.log(err)
            reject(new Error('错误'))
          })
        })
      },
      handleUploadSuccess (res, file) {
        console.log('上传成功...')
        this.showFileList = true
        this.fileList.pop()
        this.fileList.push({
          name: file.name,
          url: this.dataObj.host + '/' + this.dataObj.key.replace('${filename}', file.name)
        })
        this.emitInput(this.fileList[0].url)
      }
    }
  }
</script>

